In this work, deep grooves of more than 300 µm depth are fabricated in a high-quality Borofloat glass wafer using wet bulk micromachining in buffered HF (BHF) solution. The Cr/Au/photoresist layers are used as the etching mask. These masking layers showed very good chemical resistance to etching in BHF solution. The etchant provides smooth etched surface morphology with an excellent etch rate of 11.1 µm/min. The proposed process is very useful for the formation of deep grooves with smooth vertical sidewalls and uniform bottom surfaces. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.